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<main id="color">
<h1 class="title">color</h1>
<p class="subtitle" id="color-related-functions">Color related functions</p>
<div class="contents topic" id="contents">
<p class="topic-title">Contents</p>
<ul class="simple">
<li><p><a class="reference internal" href="#getcolorhistogram" id="id5">GetColorHistogram</a></p></li>
<li><p><a class="reference internal" href="#getnumbercolors" id="id6">GetNumberColors</a></p></li>
<li><p><a class="reference internal" href="#ispaletteimage" id="id7">IsPaletteImage</a></p></li>
</ul>
</div>
<section id="getcolorhistogram">
<h1><a class="toc-backref" href="#id5">GetColorHistogram</a></h1>
<section id="synopsis">
<h2>Synopsis</h2>
<pre class="literal-block">HistogramColorPacket *GetColorHistogram( const <a class="reference external" href="../api/types.html#image">Image</a> *, unsigned long *colors,
                                         <a class="reference external" href="../api/types.html#exceptioninfo">ExceptionInfo</a> *);</pre>
</section>
<section id="description">
<h2>Description</h2>
<p>Method GetColorHistogram returns an array of HistogramColorPacket structures
which specify the number of times each unique color occurs in the image.
The referenced colors parameter is updated with the number of unique colors
in the image. The returned array should be deallocated by the user once it
is no longer needed.</p>
<p>The format of the GetColorHistogram method is:</p>
<pre class="literal-block">HistogramColorPacket *GetColorHistogram( const <a class="reference external" href="../api/types.html#image">Image</a> *, unsigned long *colors,
                                         <a class="reference external" href="../api/types.html#exceptioninfo">ExceptionInfo</a> *);</pre>
<dl class="simple">
<dt>image:</dt>
<dd><p>The image.</p>
</dd>
<dt>colors:</dt>
<dd><p>The referenced value is updated with the with the number of
unique colors.</p>
</dd>
<dt>exception:</dt>
<dd><p>Return any errors or warnings in this structure.</p>
</dd>
</dl>
</section>
</section>
<section id="getnumbercolors">
<h1><a class="toc-backref" href="#id6">GetNumberColors</a></h1>
<section id="id1">
<h2>Synopsis</h2>
<pre class="literal-block">unsigned long GetNumberColors( const <a class="reference external" href="../api/types.html#image">Image</a> *image, FILE *file,
                               <a class="reference external" href="../api/types.html#exceptioninfo">ExceptionInfo</a> *exception );</pre>
</section>
<section id="id2">
<h2>Description</h2>
<p>Method GetNumberColors returns the number of unique colors in an image.</p>
<p>The format of the GetNumberColors method is:</p>
<pre class="literal-block">unsigned long GetNumberColors( const <a class="reference external" href="../api/types.html#image">Image</a> *image, FILE *file,
                               <a class="reference external" href="../api/types.html#exceptioninfo">ExceptionInfo</a> *exception );</pre>
<dl class="simple">
<dt>image:</dt>
<dd><p>The image.</p>
</dd>
<dt>file:</dt>
<dd><p>Write a histogram of the color distribution to this file handle.</p>
</dd>
<dt>exception:</dt>
<dd><p>Return any errors or warnings in this structure.</p>
</dd>
</dl>
</section>
</section>
<section id="ispaletteimage">
<h1><a class="toc-backref" href="#id7">IsPaletteImage</a></h1>
<section id="id3">
<h2>Synopsis</h2>
<pre class="literal-block">MagickBool IsPaletteImage( const <a class="reference external" href="../api/types.html#image">Image</a> *image, <a class="reference external" href="../api/types.html#exceptioninfo">ExceptionInfo</a> *exception );</pre>
</section>
<section id="id4">
<h2>Description</h2>
<p>Method IsPaletteImage returns True if the image is PseudoClass and has 256
unique colors or less.</p>
<p>The format of the IsPaletteImage method is:</p>
<pre class="literal-block">MagickBool IsPaletteImage( const <a class="reference external" href="../api/types.html#image">Image</a> *image, <a class="reference external" href="../api/types.html#exceptioninfo">ExceptionInfo</a> *exception );</pre>
<p>A description of each parameter follows.</p>
<dl class="simple">
<dt>status:</dt>
<dd><p>Method IsPaletteImage returns True is the image is
PseudoClass or has 256 color or less.</p>
</dd>
<dt>image:</dt>
<dd><p>The image.</p>
</dd>
<dt>exception:</dt>
<dd><p>Return any errors or warnings in this structure.</p>
</dd>
</dl>
</section>
</section>
</main>


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